This invention relates to liquid gas mixing nozzles for generating fine sprays and, more particularly, to nozzles developed for atomization of the liquid phase.
In the past, various nozzle structures have been employed for mixing a liquid and gas internally of the nozzle by imparting a whirling motion to the mixture, as shown in Pat. Nos. 738,131 to Weaver and Pat. No. 893,833 to Beckman. For many applications, such internal mixing nozzles have been found unsuitable, such as when used for spraying abrasive slurries due to the abrasive wear on the nozzle body. To overcome this problem, an external mixing nozzle for the gas and liquid was devised. One such nozzle is shown in Pat. No. 4,456,181 to Burnham, assigned to Bete Fog Nozzle, Inc., assignee of the present application.
Among the disadvantages of external mixing are the incomplete mixing of the gas and liquid with resulting liquid droplets being of relatively larger size than are acceptable for certain applications in which very fine particle size is essential, such as in cooling, humidification, spray drying, pollution control spraying and catalytic cracking of crude oil.
Accordingly, the principal object of this invention is to provide an atomizing spray nozzle constructed to achieve more complete mixing of various gas and liquid combinations and which produces more uniform mixing of the liquid and gas phases and generates finer spray droplets than were heretofore available.
Another object of this invention is to provide a nozzle of the above type which is capable of producing an atomized spray in which the average droplet size will be within the 10.mu.-500.mu. range and which has more uniform performance characteristics than the spray nozzles heretofore available.
A further object of this invention is to provide spray nozzles of the above type, characterized by abrasive resistant components which are especially adapted for combining various liquids with various gases, including crude oil with steam and abrasive slurries with compressed air.
The above and other objects and advantages of this invention will be more readily apparent from the following description read in conjunction with the accompanying drawings in which: